Field of the Invention
The invention relates to a method for modifying the geometry of the tooth flanks of a gear wheel with the aid of a tool that has a toothing that engages with the teeth of the gear wheel during a precision machining.
Description of Related Art
From DE 10 2007 043 402 A1, the contents of which are incorporated in the disclosure of the present application, it is known that corrections to the profile of the gear wheel to be respectively precision machined can be carried out extremely economically and at the same particularly effectively as regards technological aspects if the shape elements required for the respective geometrical alteration are incorporated into the tool used for the precision machining. In this connection the particular feature of this known method consists in that for the dressing, a narrow dressing wheel is used whose width compared to the width of the tooth to be respectively machined is optimally so small that the dressing wheel in the dressing process runs over the tooth flank to be machined simply in a line contact or with a contact zone reduced to a point. Owing to the use of such a narrow dressing wheel the configuration of the tool to be dressed can be shaped simply by a corresponding movement of the dressing wheel, so that in the subsequent precision machining of a gear wheel with such a dressed tool profile corrections can be produced on the machined gear wheel. The shape of the narrow dressing wheel must either agree in all parameters with the workpiece toothing or complicated and costly additional control possibilities must be included in the respective dressing device.
A comparable procedure had been suggested in DE 10 2007 043 384 for the correction of the flank line of a gear wheel.
It is known that the behaviour in use of cylindrical gear toothings can be decisively influenced not only by the macrogeometry achievable with the aforedescribed method, but also by purposefully introduced flank modifications or shape deviations occurring due to process conditions. These shape deviations include the so-called “twists”, which involve twisting of the teeth flanks. Twists are as a rule undesirable, but however can also be introduced specifically in order to improve for example the running properties of gear wheels.
Against the background of the aforedescribed prior art the object of the invention consisted in providing a method with which also complicated flank modifications can be economically implemented.